The survey, which was conducted for the Times newspaper, comes ahead of the Conservative party conference which gets underway on Sunday, when May will make a widely-anticipated speech on Britain's divorce from the EU.

Overall, just sixteen percent of respondents said May is doing well in negotiating Brexit. As many as half believe she is doing badly.

May's failure to disclose a clear strategy on Brexit negotiations is being received badly by both sides of the debate.

Just 10% of people who voted to Remain in the June referendum said May is doing well, while not even a quarter of Leave voters (24%) said the prime minister is handling Britain's exit from the 28-nation bloc well.

YouGov's research also revealed that 16% of people believed Britain will never actually leave the European Union. That figure rose to 20% among Remain voters.

It comes as one of May's own MPs, Ken Clarke, told the New Statesman this week that nobody in the government "has the first idea of what they're going to do next on the Brexit front."

The first session of the Conservative conference which BI is attending is called "Global Britain: Making a success of Brexit", with May and the three chief Brexit ministers — Boris Johnson, Liam Fox, and David Davis — all set to speak.

The prime minister will be under pressure to specify when she intends to trigger Article 50 and the type of Brexit she wants to negotiate for the country.

May still enjoys favourable ratings when it comes to her leadership in general. 85% of Tory voters said she was doing a good job overall, while 46% of UKIP voters said the same. Only 28% of Labour voters said that she was doing well, however.

85% of Tory voters said she was doing a good job overall, while 46% of UKIP voters said the same. Only 28% of Labour voters said that she was doing well, however.

The data was collected on 28 and 29 September, and surveyed 1,658 adults.